耐盐植物修复赤泥堆场的酶活性特征及影响因子分析

Characteristics and impact factors of enzyme activity in red mud storage field repaired by different salt-tolerant plants

通过开展大田试验,在赤泥堆场中种植3种耐盐植物(柽柳、碱蓬和黑麦草),考察赤泥基质中过氧化氢酶、磷酸酶、脲酶和蔗糖酶活性特征,并结合赤泥基质理化性质的变化,分析耐盐植物对赤泥堆场基质酶活性的影响。结果表明,种植柽柳、碱蓬和黑麦草后,赤泥基质pH、全盐量和电导率均有降低,全氮、有效磷和速效钾含量升高,基质中磷酸酶、脲酶、过氧化氢酶和蔗糖酶活性也有不同程度的提高,说明耐盐植物的吸盐能力和根际的分泌作用能够有效改善基质理化性质,缓解基质盐碱化程度,从而提高基质酶活性。其中,碱蓬对拜耳法赤泥的适应性优于黑麦草和柽柳,而柽柳对烧结法赤泥的适应性优于碱蓬和黑麦草。植物类型及赤泥种类均会影响基质酶活性,且植物类型对酶活性的影响大于赤泥种类。酶活性与基础理化指标有着密切关系,其中pH、电导率是影响酶活性的关键影响因子。

Through field experiments,three salt-tolerant plants(Tamarix,Suaeda salsa,and Lolium perenne) were cultivated in red mud storage field to investigate the activity characteristics of catalase,phosphatase,urease,and invertase in the red mud matrix.By analyzing the changes in the physical and chemical properties of the red mud matrix,the impact of salt-tolerant plants on the enzyme activity of the red mud matrix was assessed.The results showed that after planting Tamarix,Suaeda salsa,and Lolium perenne,the pH,total salt content,and electrical conductivity of the red mud matrix decreased,while the total nitrogen,available phosphorus,and rapidly available potassium content increased.The activities of phosphatase,urease,catalase,and invertase in the matrix also improved to varying degrees,indicating that the salt absorption capacity of salt-tolerant plants and the secretory function of their root systems could effectively improve the physical and chemical properties of the matrix,alleviate the degree of salinization,and thus enhance the enzyme activity.Among them,Suaeda salsa showed better adaptability to Bayer process red mud than Tamarix and Lolium perenne,while Tamarix had superior adaptability to sintering process red mud than Suaeda salsa and Lolium perenne.Both the type of plant and the type of red mud affected the matrix enzyme activity,with the plant type having a greater influence on enzyme activity than the type of red mud.Enzyme activity was closely related to the basic physical and chemical indicators,with pH and electrical conductivity being the key factors influencing enzyme activity.